#ifndef _PB_DECODE_H_
#define _PB_DECODE_H_
+/* pb_decode.h: Functions to decode protocol buffers. Depends on pb_decode.c.
+ * The main function is pb_decode. You will also need to create an input
+ * stream, which is easiest to do with pb_istream_from_buffer().
+ *
+ * You also need structures and their corresponding pb_field_t descriptions.
+ * These are usually generated from .proto-files with a script.
+ */
+
#include <stdbool.h>
#include "pb.h"
+#ifdef __cplusplus
+extern "C" {
+#endif
+
/* Lightweight input stream.
- * If buf is NULL, read but don't store bytes.
- * You can to provide a callback function for reading or use
+ * You can provide a callback function for reading or use
* pb_istream_from_buffer.
*
- * You can use state to store your own data (e.g. buffer pointer),
+ * Rules for callback:
+ * 1) Return false on IO errors. This will cause decoding to abort.
+ *
+ * 2) You can use state to store your own data (e.g. buffer pointer),
* and rely on pb_read to verify that no-body reads past bytes_left.
- * However, substreams may change bytes_left so don't use that to
- * compute any pointers.
+ *
+ * 3) Your callback may be used with substreams, in which case bytes_left
+ * is different than from the main stream. Don't use bytes_left to compute
+ * any pointers.
*/
struct _pb_istream_t
{
+#ifdef PB_BUFFER_ONLY
+ /* Callback pointer is not used in buffer-only configuration.
+ * Having an int pointer here allows binary compatibility but
+ * gives an error if someone tries to assign callback function.
+ */
+ int *callback;
+#else
bool (*callback)(pb_istream_t *stream, uint8_t *buf, size_t count);
+#endif
+
void *state; /* Free field for use by callback implementation */
size_t bytes_left;
+
+#ifndef PB_NO_ERRMSG
+ const char *errmsg;
+#endif
};
pb_istream_t pb_istream_from_buffer(uint8_t *buf, size_t bufsize);
bool pb_read(pb_istream_t *stream, uint8_t *buf, size_t count);
/* Decode from stream to destination struct.
+ * Returns true on success, false on any failure.
* The actual struct pointed to by dest must match the description in fields.
*/
bool pb_decode(pb_istream_t *stream, const pb_field_t fields[], void *dest_struct);
+/* Same as pb_decode, except does not initialize the destination structure
+ * to default values. This is slightly faster if you need no default values
+ * and just do memset(struct, 0, sizeof(struct)) yourself.
+ */
+bool pb_decode_noinit(pb_istream_t *stream, const pb_field_t fields[], void *dest_struct);
+
/* --- Helper functions ---
* You may want to use these from your caller or callbacks.
*/
-bool pb_decode_varint32(pb_istream_t *stream, uint32_t *dest);
-bool pb_decode_varint64(pb_istream_t *stream, uint64_t *dest);
+/* Decode the tag for the next field in the stream. Gives the wire type and
+ * field tag. At end of the message, returns false and sets eof to true. */
+bool pb_decode_tag(pb_istream_t *stream, pb_wire_type_t *wire_type, uint32_t *tag, bool *eof);
-bool pb_skip_varint(pb_istream_t *stream);
-bool pb_skip_string(pb_istream_t *stream);
+/* Skip the field payload data, given the wire type. */
+bool pb_skip_field(pb_istream_t *stream, pb_wire_type_t wire_type);
+
+/* Decode an integer in the varint format. This works for bool, enum, int32,
+ * int64, uint32 and uint64 field types. */
+bool pb_decode_varint(pb_istream_t *stream, uint64_t *dest);
+
+/* Decode an integer in the zig-zagged svarint format. This works for sint32
+ * and sint64. */
+bool pb_decode_svarint(pb_istream_t *stream, int64_t *dest);
+
+/* Decode a fixed32, sfixed32 or float value. You need to pass a pointer to
+ * a 4-byte wide C variable. */
+bool pb_decode_fixed32(pb_istream_t *stream, void *dest);
+
+/* Decode a fixed64, sfixed64 or double value. You need to pass a pointer to
+ * a 8-byte wide C variable. */
+bool pb_decode_fixed64(pb_istream_t *stream, void *dest);
-/* --- Field decoders ---
- * Each decoder takes stream and field description, and a pointer to the field
- * in the destination struct (dest = struct_addr + field->data_offset).
- * For arrays, these functions are called repeatedly.
+/* Make a limited-length substream for reading a PB_WT_STRING field. */
+bool pb_make_string_substream(pb_istream_t *stream, pb_istream_t *substream);
+void pb_close_string_substream(pb_istream_t *stream, pb_istream_t *substream);
+
+/* --- Internal functions ---
+ * These functions are not terribly useful for the average library user, but
+ * are exported to make the unit testing and extending nanopb easier.
*/
+#ifdef NANOPB_INTERNALS
bool pb_dec_varint(pb_istream_t *stream, const pb_field_t *field, void *dest);
bool pb_dec_svarint(pb_istream_t *stream, const pb_field_t *field, void *dest);
-bool pb_dec_fixed(pb_istream_t *stream, const pb_field_t *field, void *dest);
+bool pb_dec_fixed32(pb_istream_t *stream, const pb_field_t *field, void *dest);
+bool pb_dec_fixed64(pb_istream_t *stream, const pb_field_t *field, void *dest);
-bool pb_dec_bytes(pb_istream_t *stream, const pb_field_t *field, uint8_t *dest);
-bool pb_dec_string(pb_istream_t *stream, const pb_field_t *field, uint8_t *dest);
+bool pb_dec_bytes(pb_istream_t *stream, const pb_field_t *field, void *dest);
+bool pb_dec_string(pb_istream_t *stream, const pb_field_t *field, void *dest);
bool pb_dec_submessage(pb_istream_t *stream, const pb_field_t *field, void *dest);
-typedef bool (*pb_decoder_t)(pb_istream_t *stream, const pb_field_t *field, void *dest);
+bool pb_skip_varint(pb_istream_t *stream);
+bool pb_skip_string(pb_istream_t *stream);
+#endif
-/* --- Function pointers to field decoders ---
- * Order in the array must match pb_action_t LTYPE numbering.
- */
-const pb_decoder_t PB_DECODERS[PB_LTYPES_COUNT];
+#ifdef __cplusplus
+} /* extern "C" */
+#endif
#endif
Code Review / apps / agl-service-can-low-level.git / blobdiff